It looks like the package got corrupted during the download - could you please open a terminal, type sudo rm /var/cache/apt/archives/thunderbird_14.0+build1-0ubuntu0.12.04.1_i386.deb && sudo apt-get install thunderbird (to remove the broken package from the cache and force apt-get to download it again) and tell me if that works?
** Changed in: thunderbird (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1034247 Title: package thunderbird 14.0+build1-0ubuntu0.12.04.1 failed to install/upgrade: ile tar rovinato - l'archivio del pacchetto è danneggiato To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/1034247/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs